Grundfos TP Series Скачать руководство пользователя страница 13

Страница: 13 / 212

English (GB)

7.2 Pipework

Arrows on the pump housing show the direction of
flow of liquid through the pump.
The pump is suitable for mounting in horizontal
pipes.
Isolating valves should be fitted either side of the
pump to avoid draining the system if the pump needs
to be cleaned or repaired.
When installing the pipes, it must be ensured that the
pump housing is not stressed by the pipework.
The suction and discharge pipes must be of an
adequate size, taking the pump inlet pressure into
account.
To avoid sediment build-up, do not fit the pump at the
lowest point of the system.
Install the pipes so that air locks are avoided,
especially on the suction side of the pump, see fig. 2.

Fig. 2

Correct pipework on the suction side of
the pump

7.3 Bypass

If there is any danger of the pump running against a
closed discharge valve, a minimum liquid flow
through the pump should be ensured by connecting
a bypass/a drain to the discharge pipe. The drain
can for instance be connected to a tank. A minimum
flow rate equal to 10 % of the flow rate at maximum
efficiency is needed at all times.
Flow rate and head at maximum efficiency are stated
on the pump nameplate.

7.4 Foundation

Grundfos recommends to install the pump on a
concrete foundation which is heavy enough to
provide permanent and rigid support to the entire
pump. The foundation must be capable of absorbing
any vibration, normal strain or shock. As a rule of
thumb, the weight of the concrete foundation should
be 1.5 times the weight of the pump.
Place the pump on the foundation and fasten it,
see fig. 3.

Fig. 3

Foundation for TP pump

A: Expansion joint
B: Concrete pedestal
C: Vibration damper

7.5 Vibration dampening

To prevent vibrations from being transmitted to the
building and pipework, it is recommended to fit
expansion joints and vibration dampers, see fig. 3.

7.5.1 Expansion joints

Expansion joints provide the following functions:
•

Absorption of thermal expansion and contraction
of pipework caused by variations in liquid
temperature.

•

Reduction of mechanical influences in connection
with pressure surges in the pipework.

•

Isolation of structure-borne noise in the pipework
(only rubber bellows expansion joints).

The expansion joints should be fitted at a minimum
distance of 1 - 1 1/2 x DN diameter from the pump,
both on the suction and the discharge sides.
This prevents turbulence in the joints, thus ensuring
optimum suction conditions and minimum pressure
drop on the discharge side.
At high water velocities (> 5 m/s), it is recommended
to fit larger expansion joints matching the pipework.

00 22

63 019

Caution

The pump is not allowed to run against
a closed discharge valve as this will
cause an increase in temperature/
formation of steam in the pump which
may cause damage to the pump.

Caution

Expansion joints must not be fitted to
make up for inaccuracy in the
pipework, e.g. centre displacement or
misalignment of flanges.

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •

• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • •